1. Field of the Invention
The invention relates to an improved hard surface cleaner especially effective on bathroom soils, such as soap scum. The inventive hard surface cleaner benefits from a novel combination of builders, namely, a precipitating and a non-precipitating builder.
2. Brief Statement of the Related Art
A number of hard surface cleaners have been specially formulated to target bathroom soils. These include products containing liquid hypochlorite for combating mildew and fungus; products with quaternary ammonium compounds as bacteriostats; and acidic cleaners, such as those containing phosphoric or other strong mineral acids.
These cleaners will typically include buffers, dyes, fragrances, and the like in order to provide performance and/or aesthetic enhancements.
Co-pending and parent application Ser. No. 08/731,653, filed Oct. 17, 1996 now U.S. Pat. No. 5,972,876, of Robbins et al., entitled "Low Odor, Hard Surface Cleaner with Improved Soil Removal," of common assignment, discloses and claims a low odor hard surface cleaner which includes amine oxide, quaternary ammonium compound and tetrapotassium ethylenediaminetetraacetate for enhanced and proficient soil removal. Its disclosure is incorporated herein by reference thereto.
Co-pending application Ser. No. 08/807,187, filed Feb. 2, 1997 now U.S. Pat. No. 6,013,615, of Zhou et al., entitled "Antimicrobial Hard Surface Cleaner," also of common assignment, discloses and claims an antimicrobial hard surface cleaner which includes amine oxide, quaternary ammonium compound and tetrasodium EDTA, in which a critical amine oxide: EDTA ratio results in enhanced non-streaking and non-filming performance. Its disclosure is incorporated herein by reference thereto.
Mills et al., U.S. Pat. No. 5,814,591, further of common assignment, discloses and claims a hard surface cleaner which includes surfactants and tetraammonium EDTA for proficient soap scum and soil removal. Its disclosure is incorporated herein by reference thereto.
However, none of the art discloses, teaches or suggest the use of a less than completely neutralized EDTA (especially where the neutralizing agent is a potassium salt--e.g., KOH--resulting in a K.sup.+ counterion), combined with a precipitating builder (preferably, another and different potassium salt) as an effective chelating agent which additionally surprisingly enhances the soil removing, especially soap scum-removing, ability of the liquid, one phase cleaners formulated therewith. Additionally, unlike some of the prior chelating agents, the combined non-completely neutralized potassium EDTA has very low to no odor, which is a significant beneficial attribute to the inventive cleaners hereof. Moreover, none of the art discloses, teaches or suggests the unexpected speed at which the inventive cleaners work.